The present invention relates to a system that can be used to withdraw liquids from a patient in a medical environment by a means of a chest tube, and, more particularly, to a thoracic drainage system having an improved, disposable component.
There are in use today, a considerable selection of thoracic drainage systems that carry out the withdrawal of liquids from a patient. In general, after many surgical operations, there is a need to remove certain liquids from a patient and, in particular, there is a need to remove fluids from the thoracic cavity of the patient. Such fluids build up after surgery and include secretions such as blood and plasma that accumulate and must therefore be removed from the patient to prevent such build up from becoming harmful to the patient.
Typically, such systems for the removal of the fluids comprise three basic components that are used in conjunction with the chest tube and the various tubes that are used to connect those components together and to a vacuum system within the hospital. First, fluids removed from the patient via a chest tube are collected in a collection chamber where those fluids are accumulated and the collection chamber is either periodically emptied or disposed of altogether. Next, there is a water seal that is used to prevent ambient air from reaching the chest cavity as well as to provide a visual indication to the caregiver of a possible leak in the overall thoracic drainage system. Lastly, there is a vacuum control that regulates the amount of vacuum that is applied to the system from the source of vacuum provided generally by the hospital central vacuum system or may be through the use of a localized vacuum source.
In the past, the various functions of the aforementioned components were carried out by the use of three individual bottles. One of the bottles collected the liquid from the patient, a second bottle provided the function of a water seal to prevent the back flow of ambient air into the chest cavity and third bottle acted like a regulator and comprised a water manometer having a fixed height of water such that when the vacuum exceeded a predetermined level, air would pass into the water manometer and limit the level of vacuum to the thoracic drainage system and ultimately, of course, to the patient cavity. By changing the level or height of the water, different maximum levels of vacuum could be attained.
The three bottle system, however, left a considerable number of parameters undecided and was sometimes difficult and tedious to set up properly by the user that had to be trained in the set up procedures. Accordingly, to counter those problems, various systems were devised that integrated all of the aforementioned three functions into a single apparatus. Thus, the usual apparatus today collectively incorporates a collection container or chamber, a water seal and a means of regulating the amount of vacuum to the overall system. An example of such apparatus is shown and described in U.S. Pat. No. 3,363,626 of Bidwell et al where a single, disposable underwater drainage unit is disclosed where a transparent plastic unit is provided to carry out all of the steps of a collection container, an underwater seal chamber and a water manometer incorporated therein and which eliminates the set up procedures used with the three bottle system and thus reduces the possibilities of an incorrect coupling or filling of the individual bottles. Thus, the emphasis of such systems is in the incorporation into a single apparatus, of all of the three functions of the normal thoracic drainage system, that is, the collection chamber, the water seal and water manometer
Typical today of such systems is the Pleur-evac apparatus manufactured and marketed by Deknatel, Snowden, Pencer or DSP and the entire apparatus is constructed so as to be disposable and to integrate into a single apparatus, the functions of the water manometer, the water seal and the collection chamber. Other such apparatus are commercially marketed by Sherwood Medical and Baxter Healthcare and all are typical of the systems currently marketed for the drainage of the thoracic cavity and all incorporate the functions of a vacuum regulator, water seal and collection chamber into an integrated apparatus. With such integrated systems, however, the overall cost of the apparatus is still relatively high and it is not always cost effective to dispose of the entire apparatus after each patient. There is, in such systems a considerable expenditure of money that is totally lost after use on one patient. Even though easier to assemble and possibly less expensive than having three separate components for the three functions, the overall cost of an integrated apparatus still is quite substantial and it would be advantageous to have a thoracic drainage system serving the full functions of such a system but at a lesser cost to the hospital.
Accordingly, it would be advantageous to have a plural drainage apparatus or system that can employ, to the extent possible, standard components, such as, for example, the collection container since collection containers are readily available by themselves and are very inexpensive, as compared with an entire thoracic drainage apparatus and the disposal of a collection chamber can be very cost efficient to simply be discarded after its use with an individual patient. As such, it would be a cost savings to take advantage of the many collection chambers that are currently available in the marketplace from a number of companies that simply collect fluids for disposal and due to the high usage of such collection chambers, the cost of such containers is very low.
There is also available, an improved vacuum regulator that is specially adapted for use with thoracic drainage and which is marketed by Datex-Ohmeda, Inc, the present assignee, and which is capable of providing the precise levels and ranges of vacuum needed for thoracic drainage having the characteristics of relatively high flow and low impedance, i.e. a level of vacuum between a negative pressure of about 5 cm. water to about 50 cm. water and therefore is a reusable component that can be used with multiple patients and not disposed of after each use. By the use of such a regulator, that component can be used repetitively and the cost, therefore, not wasted after the use on a single patient.
In addition, it is advantage for the caregiver to continually visually monitor the water seal function of the apparatus as it provides an indication of the presence of a leak in the overall system. For example, if bubbles are continually being formed in the water seal component, it is generally an indication that there is an air leak into the system and the leak can thereafter be traced by occluding the drainage tubing at various locations to ascertain the location of that leak. However, with an integrated system, the collection chamber where the liquids from the patient are being collected must be located below the patient, or, more specifically, below the particular cavity that is being drained by the system, in order to prevent a siphoning effect that can return liquid accumulated in the collection chamber back to the patient. As such, the typical integrated apparatus must itself be located below the patient, generally on the floor of the patient room and thus it is quite inconvenient for the caregiver to be able to visually check the functioning of the water seal to ascertain and verify its proper operation. It would, obviously be more advantageous if the water seal component or function were located at a convenient height for the caregiver and preferable at the eye level of that caregiver.
Too, with the present integrated thoracic drainage systems, in the event it is necessary to move a patient from one location to another, the apparatus must, of course, be disconnected from the source of vacuum in order to make such movement. With the integrated apparatus, the apparatus itself is also normally disconnected as it is cumbersome to move that apparatus that includes various liquids within the collection chamber and the water manometer along with the patent, however, it is important that the water seal be maintained to insure that ambient air does not enter the patient cavity during the move. Accordingly, since it is so cumbersome to move the typical integrated apparatus containing liquid in the various chambers and containers, there is often a makeshift water seal that is assembled on site by the caregiver to place the patient tube into a container of water to keep the water seal function during the move. Obviously, such an arrangement is not particularly desirable as it is difficult to assemble the water seal and the movement can cause the makeshift water seal to spill or become disconnected from the patient.
It would, therefore, also be advantageous to be able to easily separate the water seal function from the other component or components so as to only maintain that water seal function for the protection of the patient in transit without involving the other components, that is, to continue the function of the water seal as the patient is in actual transit without also carrying along the collection container.
There is, therefore, clearly a need for some type of apparatus that can be used in a thoracic drainage system that provides accurate, safe drainage of the patient by means of a chest tube or the like and which can make use of a standard collection chamber or container that is cost effective so as to be disposable after each patient, a reusable vacuum regulator that can be used with a plurality of patients and a water seal component that can be a separate, inexpensive component that is fully cost effective as a disposable device but, additionally, can be located above the patient, preferable at the eye level of the caregiver so that it can be visually monitored easily and without inconvenience to that caregiver.
Accordingly, the present invention relates to a method and apparatus that is used in carrying out the thoracic drainage of a patient in a hospital environment. The present apparatus and method is used with a chest tube to drain the thoracic cavity of the patient and can be used with a standard collection container to accumulate the fluids drained from the patient. The vacuum is regulated and controlled to the desired level of vacuum by means of a reusable thoracic drainage regulator based on a construction that is presently available commercially to the market. As to the remaining components, a unique disposable water seal function is provided by having an inexpensive construction of a water seal that can be a separate component, pre-filled with a sterile liquid, and which is comprised of easily mass produced molded parts.
With the water seal component manufactured as a disposable, independent device, it can be seen that the water seal can therefore be located at any level with respect to the patient cavity being drained since the normal fluid collection container is a separate component and can be located at the desired level below the patient cavity being drained and yet the disposable water seal component can be at any elevated position above the patient and conveniently located at the eye level of the caregiver to improve the ability of that caregiver to continuously monitor the water seal and its functioning to verify that no leaks are occurring in the system.
In a further embodiment of the present invention, the disposable water seal component can be built into the housing of the thoracic vacuum regulator by a unique interlocking arrangement and thus the thoracic regulator and the water seal chamber can be manufactured and supplied as a single integrated unit, however, even then, the water seal chamber is adapted to be readily removable from the housing of the vacuum regulator and disposed of cost effectively. Again, therefore, with the combined water seal chamber and thoracic vacuum regulator embodiment, the water seal chamber can be located at the eye level of the caregiver since that location is the normal elevation of a vacuum regulator affixed to the central vacuum system of a hospital.
As a further feature of the built-in embodiment, since the water seal is easily detachable from the thoracic vacuum regulator, in the event it becomes necessary to move a patient, that water seal component can be detached from the housing combining it with the thoracic vacuum regulator and simply hung on a standard IV post that is normally on the bed or otherwise accompanying the patient during the move. As such, the water seal function can easily be continued as the patient is moved and yet there is no need to move the collection chamber or the remaining components that make up the thoracic vacuum system.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention.